In recent years, flat panel displays have been utilized in various products and fields, and there are demands for flat panel displays having even larger sizes, even higher picture quality, and even lower power consumption.
In view of such circumstances, organic electroluminescence (referred to as EL below) display devices provided with organic EL elements utilizing the electro luminescence of organic materials are attracting much attention as flat panel displays due to their excellent qualities, such as low voltage driving, high responsiveness, and self-luminosity, while being in a completely solid state.
For example, in the case of an active-matrix organic EL display device, a thin-filmed organic EL element is disposed on a substrate on which thin film transistors (TFT) are provided. The organic EL element includes an organic EL layer including a light-emitting layer layered between a pair of electrodes. The TFT is connected with either side of the pair of electrodes. Then, voltage is applied across the pair of electrodes to make the light-emitting layer emit light, whereby image display is performed.
Furthermore, for the conventional organic EL display device stated above, it is proposed to seal the organic EL elements to prevent the organic EL elements from deteriorating due to moisture or oxygen.
More specifically, the conventional organic EL display device stated above includes an organic EL element, a substrate including the organic EL element mounted thereon, and a sealing substrate provided facing the substrate, as stated, for example, in PTL 1 stated below. Furthermore, the conventional organic EL display device has a frame-shaped glass frit provided between the substrate and the sealing substrate and surrounding the organic EL element, whereby the organic EL element can be sealed.